In a free space optical (FSO) communications network having a bent pipe architecture, data is transferred between relay nodes via optical space links. At each relay node, the data is re-amplified, but not modulated or demodulated.
On an optical link between a ground station and a relay satellite, outages can occur due to the physical nature of the atmosphere (e.g., cloud blockage, and clear air turbulence effects so severe that the optical link cannot function properly). An outage may be characterized by high bit errors or a total loss of data. In anticipation of a link outage at a single ground station, the network may be reconfigured by terminating an existing optical link and re-establishing a new optical link.
Recent reconfiguration approaches take time. Re-establishing a new optical link requires a spatial and signal acquisition that can take minutes to perform. As the reconfiguration is being performed, data is being buffered to prevent data loss. At a 100 Gbps data rate and a one minute switching time, six terabits of data must be buffered. The added latency from the buffering affects the network traffic and adds the potential for loss of data.